Concentrating surface



D. W. SHEPHERD.

CONCENTRATING SURFACE. APPLICATION mso SEPT. z. 1920.

:DANIEL w. SHEPHERD, or rocA'rELLo, IDAHO.l

.CONCENTRATING SURFACE.

l Application filed September 7, 1920. Serial No. 408,691.

To all Lo/Lam it may concern:

Be it known that I, DANIEL W. SHEPHERD, a citizen of the United States, residing at Pocatello, in the county of Bannock and State of Idaho, have invented certain new and useful Improvements in Concentrating Surfaces, of which the following is a specification, referencev being had to the accompanying drawings.

This invention relates Vto concentrating belts, tables and other surfaces over whichV material to be concentrated travels, and par-V ticularly to a particular manner of forming the surface of the concentrating belt, table or the like.

The general object of my invention is to provide an improved concentrating surface .wherein the rubber, canvas or other surfaceV of the concentrating table or concentrating` belt or apron is covered with sawdust held in place by means of cementgthis sawdust acting to hold the concentrates while permitting the silt, sand and other light particles to be washed down and off the belt or table.

Other objects will appeal' in the course of the following description.

My invention is illustrated in the accom-V panying drawings, wherein Figure l is a longitudinal sectional view of a concentrating surface constructed in accordance with my invention;

Figure 2 is a top plan view of the concentrating surface.

My invention may be applied to y'concentrating decks or tables in mills or to concentrating belts or to sluice boxes. I have illustrated myinvention as applied to a concentrating belt, but it is to be understood that I donot wish to be limited to the illustrated application of this surface. In the drawings, 10 designates a belt or layer which may be of rubber. canvas or any other suitable fabric, and which is coated with an initially soft and thin coating` of rubber cement, designated generally l2, and sprinkled over this cement, when soft, is sawdust 13, the sawdust being very thickly scattered upon the surface of the fabric, so that the fabric is practically covered with the sawdust and the face of the fabric roughened thereby.

This belt or layer covered with sawdust as Specification of Letters Patent.

Patented aan.' si',V 1922.

for use on Snake River gold bearing sands which contain fine flour gold, and this has described has been .particularly designedv been found extremely successful. All of the Y gray sand and almost all. of the slit iiows over'this surface withoutbeing caught by the sawdust, but the black concentrates con- ,l

taining gold andother valuable metals are caught, the sawdust making a rough surface'y and having pitholes and rough edges which hold the concentrates. i

In order to get the concentrates from the.

sawdust, the concentrates are rinsed oif with water, or the belt,fwh`ere a concentrating belt is used, may be runV throughv a hutch containing water. .It will'be understood, of

course, that where a belt is used, the mixed material is delivered upon the belt, which has suflicient inclination4 so that the mate-v rial with the water will tend to flow towards concentrates are washedofl" in the'usual box.

into which the belt dips.

l. A concentratingelement h* ving a` sur' face .over which the ore lis adapted to flow composed of a roughly granular ibrousmaterial adhering to the element and covering the same. i 'v 2. A concentrating element having a surface over which the ore is adapted to flowy composed of fabricand a covering adhering 'thereto composed of comminuted, relatively rough particles of fibrous material.

A vconcentrating element over which the ore is adapted to' flow consisting ot a layer of fabric, cement coreringthe .face f of said fabric, and sawdust .distributed closely over the fabric and caused to. adhere f thereto by the cement.

4. A concentrating surfaceover which the v ore is adapted to fiow having a layer of sawdustl thickly distributed thereon and adi hering thereto.

In testimony whereof I hereunto affix my signature.

DANIEL w. SHEPHERD .1 

